Derpy first appeared in the pilot of season 1 with her signature eyes as the combination of a joke by one of the animators, and a blocking issue, removing the pony that should have been in front of her. Derpys first appearance was quickly picked up on 4chan, and thread after thread were made in her name. Studio B quickly picked up on the fans love of this derp-eyed pony and began putting her in the background of episodes as a “where’s waldo” type game for the fans. This led to her first “canon” naming as Lauren Faust auctioned off a sketch saved as “Derpy11”. The back and forth between the animator and fans continued until Episode 14 of Season 2, “the last round up” where the animators decided to fully embrace the fanbase and give Derpy a speaking line. Unfortunately the reaction was not as much love and tolerance as controversy. Hasbro began to take away Derpy’s lines and straighten her eyes as fans claimed they held offensive aspects and insulted the disabled. This only sparked more negative tension, as petitions began to form to get her voice back or take it off, and although the original can still be found quite easily, the iTunes episode had Derpy censored and changed. Although this did only enrage more bronies, many members of the staff went out of their way to ensure Derpy’s safety as a hide and go seek game for all the bronies to still enjoy.
Or, you know, whatever.